Frictionally engaged slide box



June 19, 1956 M KESSLER FRICTIONALLY ENGAGED SLIDE BOX Filed May 27, 1953 ATTORNEY FRICTIONALLY ENGAGED SLIDE BOX Milton Kessler, Youngstown, Ohio Application May 27, 1953, Serial No. 357,741

1 Claim. (Cl. 229-9) This invention relates to a slide box comprising a tray or drawer slidable in an open ended sleeve, similar to the well-known match box construction, and has for its primary object the provision of friction means in such a slide box for insuring adequate engagement between the tray or drawer and the cover or sleeve, so that the former cannot accidentally fall or slip out of the latter with resultant loss of the contents.

The invention has particular reference to slide boxes wherein the sleeve and drawer are made of different dimensional tolerances. For example, a preferred slide box according to the invention is composed of a sleeve made of extruded plastic material, which by its inherent method of manufacture is held to very close tolerances in the order of of an inch, while the typical drawer is made of cardboard pasted together with paper, which cannot, of course, be held to such close tolerances. As a consequence, in assembling slide box and drawer, in a certain number of cases, the drawer will be a loose fit in the box and will consequently tend to fall out. The opposite case, of the drawer being too large for the sleeve, is controlled by setting a maximum dimension for the drawer, and in any event, will be automatically controlled in assembly since drawers which cannot fit into the sleeves must necessarily be discarded. To discard all of the drawers which are so small as to be loose in the sleeve would result in unnecessary Waste, and greatly increase the cost of production, which is an essential factor in the case of these very inexpensive items intended primarily for use as containers. As the plastic material of the sleeve is relatively flexible, it would, of course, be possible to distort its shape somewhat, so as to provide a friction fit between the inner surface of the sleeve and the enclosed drawer. However, the inner surface of an extruded sleeve is inherently very smooth, and in practice the above expedient does not provide sufficient frictional engagement between the two components of the slide box to insure that the box will remain closed under normal conditions of transportation and handling. The provision of separate spring friction means would materially increase the cost of production of the item and it must be kept in mind that cost is an absolutely essential factor in the practical production of these items. Any appreciable increase in the cost of production is therefore not tolerable in a solution in the above problem, due to the highly competitive nature of the item and the loss of competitive position in comparison with alternative types of containers.

According to the invention, the necessary friction is provided by piercing through the plastic sides of the cover or sleeve from the outside toward the inside so as to cause a sharp eruption of the plastic material with torn edges protruding toward the inside of the sleeve. The sharp edges engaging but not tearing the softer material of the drawer serve very effectively to compensate for the dimensional differences in the sleeve and drawer which are encountered in actual practice. This method can be accomplished without altering or alfectnited States Patent 'ice ing the extrusion process in any way, and does not even require the insertion of a mandrel into the sleeve, so that it adds practically nothing to the expense of labor, material, or tools required. It can be added as an additional step at the end of the extruder line and can be accomplished by simple mechanism designed for the purpose, or manually by inexpensive unskilled labor.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawing, in which:

Fig. l is a perspective view of a slide box with the drawer partly open;

Fig. 2 is an end view of the sleeve of the slide box shown in Fig. 1, showing the pierced friction elements; Fig. 3 is a view taken along line 3-3 of Fig. 2; and

Fig. 4 is an enlarged cross-section view of a portion of Fig. 3, showing the details of the pierced or struckthrough friction element.

Referring to Fig. l, the slide box according to the invention is shown. This typically comprises an extruded plastic sleeve 3 open at both ends and inexpensively formed by cutting off pieces of a continuous rectangular tube of extruded material. It is assembled together with a drawer or tray 2 as shown to form a slide box. Sleeve 3 is usually made of transparent material for the purpose of displaying the contents of the box while protecting the same. The tray 2 is typically chiefly made of cardboard pasted together with paper in conventional fashion. With this or similar inexpensive constructions, it is apparent that the tray cannot profitably be held to close dimensional tolerances, while the method of manufacture of the sleeve, though inexpensive, is inherently dimensionally very accurate. It therefore necessarily results that in practical inexpensive assembly of the boxes, some of the trays will be found to be so loose as to be unsatisfactory. In order to eliminate this, I provide a pierced-through or struckin dimple as shown at 4 and 5, the dimples being located preferably at the corners and the box so assembled that the dimples will engage the bottom corners of the drawer 2. With this construction the dimples tend to press somewhat in the direction of maximum rigidity of the tray, that is, along the line of the bottom of the tray, and they are restrained from too easy flexing away from each other by the bottom portion 6 of the sleeve. This assures necessary rigidity and firmness of frictional engagement, to a greater extent than would be possible if the dimples were placed in or near the center of the walls of the sleeve, since it must be remembered that the sleeve is made of quite thin and flexible material.

It is an essential feature of the invention that in forming the dimple, the material is pierced entirely through to leave an inwardly producing jagged edge as shown at 7 in Fig. 4, as otherwise the necessary insurance of adequate frictional engagement under ordinary conditions cannot be obtained. The plastic material of the sleeve, although harder than the paper and cardboard of the tray, is still relatively soft material and in practice does not tear the paper of the sleeve, but only depresses it somewhat, yet the sharp jagged points of the broken edge 7 serve to insure very positive frictional engagement so that the drawer is not easily displaced, even when it is filled with relatively heavy material such as nuts or bolts, and subject to such jars as occur during transportation or ordinary moderately rough handling.

It will be apparent that the embodiments shown are only exemplary and that various modifications can be made in construction and arrangement within the scope of my invention as defined in the appended claim.

I claim:

A rectangular slide box comprising a cardboard-andpaper drawer having an open top, a bottom, at least two sides, and two end walls, a unitary sleeve cover of thinwalled extruded plastic material having much greater stiffness than the drawer material and having a smooth inside surface conforming in shape and dimension to the outside dimension of said bottom and two sides so that the drawer fits slidingly in said sleeve cover; and friction means consisting of two friction elements for insuring frictional engagement between said cover and said drawer, each said friction element comprising a bentin portion in said sleeve cover protruding from said inside surfaee toward said drawer, said bent-in portion being perforated so as to produce sharp edges which frictionally engage the surfaces of the drawer by depressing same without tearing, said bent-in portions being formed References Cited in the file of this patent UNITED STATES PATENTS 542,903 Truax July 18, 1895 1,562,497 Derry Nov. 24, 1925 1,682,449 Vest Aug. 28, 1928 1,762,310 Rutkowski June 10, 1930 2,082,564 Benoit June 1, 1937 2,690,199 Bennorth Sept. '28, 1954 

